UHD brings many benefits, but also the kind of disadvantages like any new technology,
especially in its beginning. The benefits of higher resolution logically have a greater amount
of information on the screen and therefore a more realistic view, especially on the diagonals
that are larger than 140 cm (55″) and where full HD resolution loses the impression of high
sharpness. This is why manufacturers have presented the first UHDTVs in diagonals of 84″
(213 cm) that they would now be available in smaller dimensions—140 cm (55″) and 165 cm
(65″). UHD on smaller diagonals does not have much sense because the density of information
is too large and the average viewing distances further details cannot be seen in relation to the
full HD content.
Many parameters have effect on the realism of images, and among them resolution is not most
important element. Number of pixels has a smaller impact on how we experience the image
of other parameters, such as increased dynamic range, the range and depth of color, as well as
the number of frames per second. UHD used Rec. 2020 standard color range in contrast to the
definition used by Rec. 709 standard. Rec. 2020 defines a bit depth of either 10 bits per sample
or 12 bits per sample. Rec. 2020 specifies the following frame rates: 120p, 119.88p, 100p, 60p,
59.94p, 50p, 30p, 29.97p, 25p, 24p, 23.976p [18].
Table 6 [18] provides an overview of the main
characteristics of images in HDTV, 4K and 8K UHDTV.
